Batman is the 1989 film adaptation of the DC Comics character. Directed by Tim Burton, Michael Keaton stars as the Caped Crusader, who matches wits with the Joker (Jack Nicholson). This cycle of Batman films would span 4 films (including Batman Returns, Batman Forever and Batman & Robin) before Christopher Nolan's "reboot" of the franchise in 2005 with Batman Begins.
The following weapons were used in the film Batman:
Bob (Tracey Walter) uses a Colt M1911A1 throughout the movie on several occasions. A random goon also uses one later in the movie.
Colt New Service
Jack Napier/The Joker (Jack Nicholson) uses a Colt New Service throughout most of the film including the BANG flag gun at the film's climax and flashback, where young Napier (played by Hugo E. Blick) shoots Bruce Wayne's parents. The only exception is one small edit when he pulls back the hammer in the Axis Chemical plant. A different revolver was used for this one shot.
The Joker (Jack Nicholson) uses a Smith & Wesson Model 15-3 with a custom 21 inch barrel to shoot down the Batwing. We later see that the gun has a telescoping barrel when the Joker collapses it.
Smith & Wesson Model 19 Revolvers appear frequently throughout the film, notably in the hands of a mugger at the beginning of the film. Another Model 19 is seen carried by Lt. Eckhardt (William Hootkins).
Some of Joker's goons are armed with what appear to be Webley Mk IV revolvers in some scenes.
M1928 Thompson
The Joker's goons use M1928 Thompson Submachine Guns multiple times throughout the movie.
Krieghoff Model L flare pistol
The Joker uses a Krieghoff Model L flare pistol to shoot his TV, then proceeds to hand it to Bob.
Browning M1919
The guns that pop out of the Batmobile's fenders are two Browning M1919's. Seen toward the end of the movie as the Batmobile is entering the chemical plant.
GE M134 Minigun
Batman (Michael Keaton) has a mocked-up GE M134 Minigun on the Batwing, and uses it to shoot at The Joker near the end of the movie.
IMI Uzi
On Jack Napier's desk at his hideout, one of the photographs on his desk shows a dead soldier affected by one of the Joker's prototype gasses carrying an Uzi with a unfolded stock.
Unidentified Revolver
Carl Grissom (Jack Palance) tries to reach for an unidentified revolver.